1. The Field of the Invention
The present invention relates to mixing systems that can be used in the biopharmaceutical industry.
2. The Relevant Technology
The biopharmaceutical industry uses a broad range of mixing systems for a variety of processes such as in the preparation of media and buffers and in the growing of cells and microorganisms in bioreactors. Many conventional mixing systems, including bioreactors, comprise a rigid tank that can be sealed closed. A drive shaft with impeller is rotatably disposed within the tank. The impeller functions to suspend and mix the components.
In many cases, great care must be taken to sterilize and maintain the sterility of the mixing system so that the culture or other product does not become contaminated. Accordingly, between the production of different batches, the mixing tank, mixer, and all other reusable components that contact the processed material must be carefully cleaned to avoid any cross contamination. The cleaning of the structural components is labor intensive, time consuming, and costly. For example, the cleaning can require the use of chemical cleaners such as sodium hydroxide and may require steam sterilization as well. The use of chemical cleaners has the additional challenge of being relatively dangerous, and cleaning agents can be difficult and/or expensive to dispose of once used.
The operation and maintenance of such mixing systems can be daunting for many facilities, especially where it is desirable to make a large number of smaller batches. Accordingly, what is needed are mixing systems that require minimum cleaning or sterilization, can be used for mixing or suspending a broad range of materials, can consistently provide a sterile environment, and are relatively inexpensive and easy to operate.